Elia, the operator of the Belgian high voltage network, and Britain's National Grid have been working on the project, the Nemo Link, for a decade. The Link is 140 km long and connects Richborough in the UK with Bruges. 130 km are in the North Sea. So far 628 million euros has been invested.
Last night 1 gigawatt of electricity started to be sent to the UK and that is around the production of one nuclear power plant. The Link can work in both directions. In the event of scarcity here supplies can also be brought to Belgium. Elia's Chris Peeters is relieved the link is now operational especially because of the recent difficulties in Belgian nuclear power plants and worries the lights could go out.
Chris Peeters believes the Link could also help to cut Belgian electricity prices that historically have been high. Belgium is set to remain a net importer of electricity underlining the Link's importance.
Of course Brexit throws up new challenges. Elia is examining the implications. Electricity will continue to be supplied, but depending on the agreement between Belgium and the UK the mechanism may differ.
Mr Peeters reassures us that Elia and National Grid are ready for any scenario from a Hard Brexit to the abandonment of Brexit altogether.